Hydrogen gas-cooling device

Abstract

A hydrogen gas-cooling device of the present invention includes, a heat exchanger that perform beat exchange between a hydrogen gas and a liquefied gas to cool a hydrogen gas; and a head tank that stores the liquefied gas supplied to the heat exchanger, wherein the heat exchanger has double pipe structure in which the hydrogen gas flows in an inner pipe, an outer pipe is filled with the liquefied gas, the pipe axis of the double pipe structure is vertically or obliquely arranged, a liquefied gas supply pipe that supplies the liquefied gas from the head tank is connected to a bottom part of the outer tube, and a return pipe that returns the liquefied gas to the head tank is provided at a position upper than that of the bottom part of the outer pipe.

Description

TECHNICAL FIELD[0001]The present invention relates to a hydrogen gas-cooling device that is used to cool a hydrogen gas to be supplied to a hydrogen automobile, etc.[0002]Priority is claimed on Japanese Patent Application No. 2007-111562, filed Apr. 20, 2007, the content of which is incorporated herein by reference,BACKGROUND ART[0003]In a hydrogen automobile, it is required to fill a fuel tart with a hydrogen gas with a high pressure. When a fuel tank is filled with a hydrogen gas) the increase in the temperature occurs due to adiabatic compression. Moreover, a hydrogen gas is different from other conventional gases, and has the property that the adiabatic compression thereof causes the increase in the temperature due to Joule-Thomson effect.[0004]When the supply flow rate of a hydrogen gas is set high in order to improve the efficiency of filling operation, it is required to cool a hydrogen gas to a range from −30° C. to −40° C. before filling a fuel tank because the temperature o...

AI Technical Summary

Benefits of technology

[0020]According to the present invention, with the cooling of a hydrogen gas within the heat exchanger, a part of the liquefied gas within the outer pipe is evaporated, and the overall apparent density decreases. Therefore, the evaporated liquefied gas is spontaneously moved upward, and the liquefied gas is spontaneously circulated between the heat exchanger and the head tank. In this way, the liquefied gas is always moved within the overall outer pipe, resulting in the increase in the film heat-transfer coefficient on the side of the liquefied gas and the decrease in the necessary heat-transfer area. Accordingly, the heat transfer can be downsized, and the power for the supply of the liquefied gas is unncessary. In addition, the heat loss in the steady state is small, and therefore, the consumption quantity of the liquefied gas can be reduced.

[0021]By using the heat exchanger with the double pipe structure, the spacing between the outer pipe and the inner pipe therein can be shortened to for example about 20 mm. Therefore, the hold-up quantity (i.e. stored quantity) of the liquefied gas can be reduced to about 10-20 liters, and it is possible to shorten the time for the preparation of the liquefied gas during the start and the times for the discharge and beating when the liquefied gas is cleared off after the end of the operation.

[0022]In addition, by forming bellows in a part of the outer pipe, it is possible to cancel the elongation and contraction of the outer pipe and the inner pipe in the case of the temperature change of the heat exchanger

[0023]Furthermore, by providing two or more of the return pipes at different positions in a vertical direction of the outer pipe, it is possible to change effective heat-transfer area according to need, to thereby control the temperature of the hydrogen gas at the exit of the heat exchanger. In addition, by providing the bypass pipe to mix the uncooled hydrogen gas with the cooled hydrogen gas, it is possible to control the temperate of the cooled hydrogen gas.

Problems solved by technology

However, in the aforementioned hydrogen gas-cooling device, there are problems in that the overall facilities are enlarged, the consumption quantity of a refrigerant that is liquid nitrogen increases, and the starting time and the termination time are elongated.

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